In a storage structure in a storage facility for semiconductor containers such as the one described above, inactive gas is supplied, in some cases, into the interior space of the containers stored in the holding space, or to a storage location, which can be opened and closed, for storing the containers within the holding space, in order to lower the oxygen concentration in the areas surrounding the semiconductor substrates to reduce deterioration of semiconductor substrates in the containers due to oxidization. In such cases, because the inactive gas in the containers or in the storage locations flows out into the holding space, the concentration of the inactive gas in the air in the holding space is higher than the concentration of the inactive gas contained in the air in the exterior space outside of the holding space.
In addition, since the purpose of the storage structure is to temporarily store containers until they are ready to be processed by processing devices etc. provided in the exterior space, or to be carried out, the storage structure needs to be configured such that containers can be carried out to, and carried in from, the exterior space. For this purpose, a first opening for allowing containers being carried into or out of the storage structure to pass or be moved through is formed in a partitioning wall. When such an opening exists, there is a possibility that air in the holding space, whose inactive gas concentration is relatively high, may flow out to the exterior space.
On the other hand, since a worker may work in the exterior space, it is preferable to prevent the air in holding space from flowing out to the exterior space to the extent possible, in order to maintain a safe work environment.
To this end, as disclosed in, for example, JP Publication of Application No. H10-172873 (Patent Document 1), a storage structure is proposed in which the conveyance port 18 (first opening) has a door which can be opened and closed to prevent the air in the holding space from flowing out to the exterior space.